- The peripheral myelin gene PMP-22/GAS-3 is duplicated in Charcot-Marie-Tooth disease type 1A. Valentijn, L.J., Bolhuis, P.A., Zorn, I., Hoogendijk, J.E., van den Bosch, N., Hensels, G.W., Stanton, V.P., Housman, D.E., Fischbeck, K.H., Ross, D.A. Nat. Genet. (1992)